651
|
Hanski I, von Hertzen L, Fyhrquist N, Koskinen K, Torppa K, Laatikainen T, Karisola P, Auvinen P, Paulin L, Mäkelä MJ, Vartiainen E, Kosunen TU, Alenius H, Haahtela T. Environmental biodiversity, human microbiota, and allergy are interrelated. Proc Natl Acad Sci U S A 2012; 109:8334-9. [PMID: 22566627 PMCID: PMC3361383 DOI: 10.1073/pnas.1205624109] [Citation(s) in RCA: 576] [Impact Index Per Article: 48.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Rapidly declining biodiversity may be a contributing factor to another global megatrend--the rapidly increasing prevalence of allergies and other chronic inflammatory diseases among urban populations worldwide. According to the "biodiversity hypothesis," reduced contact of people with natural environmental features and biodiversity may adversely affect the human commensal microbiota and its immunomodulatory capacity. Analyzing atopic sensitization (i.e., allergic disposition) in a random sample of adolescents living in a heterogeneous region of 100 × 150 km, we show that environmental biodiversity in the surroundings of the study subjects' homes influenced the composition of the bacterial classes on their skin. Compared with healthy individuals, atopic individuals had lower environmental biodiversity in the surroundings of their homes and significantly lower generic diversity of gammaproteobacteria on their skin. The functional role of the gram-negative gammaproteobacteria is supported by in vitro measurements of expression of IL-10, a key anti-inflammatory cytokine in immunologic tolerance, in peripheral blood mononuclear cells. In healthy, but not in atopic, individuals, IL-10 expression was positively correlated with the abundance of the gammaproteobacterial genus Acinetobacter on the skin. These results raise fundamental questions about the consequences of biodiversity loss for both allergic conditions and public health in general.
Collapse
Affiliation(s)
- Ilkka Hanski
- Department of Biosciences, University of Helsinki, FI-00014 Helsinki, Finland
| | - Leena von Hertzen
- Skin and Allergy Hospital, Helsinki University Central Hospital, FI-00029 Helsinki, Finland
| | - Nanna Fyhrquist
- Finnish Institute of Occupational Health, FI-00250 Helsinki, Finland
| | - Kaisa Koskinen
- Institute of Biotechnology, University of Helsinki, FI-00014 Helsinki, Finland
| | - Kaisa Torppa
- Department of Biosciences, University of Helsinki, FI-00014 Helsinki, Finland
| | - Tiina Laatikainen
- National Institute for Health and Welfare, FI-00271 Helsinki, Finland; and
| | - Piia Karisola
- Finnish Institute of Occupational Health, FI-00250 Helsinki, Finland
| | - Petri Auvinen
- Institute of Biotechnology, University of Helsinki, FI-00014 Helsinki, Finland
| | - Lars Paulin
- Institute of Biotechnology, University of Helsinki, FI-00014 Helsinki, Finland
| | - Mika J. Mäkelä
- Skin and Allergy Hospital, Helsinki University Central Hospital, FI-00029 Helsinki, Finland
| | - Erkki Vartiainen
- National Institute for Health and Welfare, FI-00271 Helsinki, Finland; and
| | - Timo U. Kosunen
- Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki, FI-00014 Helsinki, Finland
| | - Harri Alenius
- Finnish Institute of Occupational Health, FI-00250 Helsinki, Finland
| | - Tari Haahtela
- Skin and Allergy Hospital, Helsinki University Central Hospital, FI-00029 Helsinki, Finland
| |
Collapse
|
652
|
Affiliation(s)
| | - Tatyana Golovkina
- Department of Microbiology, University of Chicago, Chicago, Illinois, United States
- * E-mail:
| |
Collapse
|
653
|
Andersen V, Egeberg R, Tjønneland A, Vogel U. Interaction between interleukin-10 (IL-10) polymorphisms and dietary fibre in relation to risk of colorectal cancer in a Danish case-cohort study. BMC Cancer 2012; 12:183. [PMID: 22594912 PMCID: PMC3472168 DOI: 10.1186/1471-2407-12-183] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Accepted: 05/17/2012] [Indexed: 12/21/2022] Open
Abstract
Background More than 50% of the colorectal cancer (CRC) etiology has been attributed to diet. Established or suspected dietary factors modifying risk of CRC are red meat, cereals, fish, and fibre. Diet and lifestyle may be linked to cancer through inflammation. Interleukin-10 (IL-10) is an anti-inflammatory cytokine. We wanted to test if dietary factors and IL10 polymorphisms interact in relation to colorectal carcinogenesis. Methods The functional IL10 polymorphism C-592A (rs1800872) and the marker rs3024505 were assessed in relation to diet and lifestyle in a nested case-cohort study of 378 CRC cases and 775 randomly selected participants from a prospective study of 57,053 persons. Genotyping data on the IL10 polymorphism C-592A, smoking and non-steroidal anti-inflammatory drugs (NSAID) was retrieved from Vogel et al. (Mutat Res, 2007; 624:88). Incidence rate ratios (IRR) and 95% Confidence Interval (95% CI) were calculated. Results No associations were found between the IL10 rs3024505 polymorphism and risk of CRC. There was interaction between rs3024505 and dietary fibre (P-value for interaction = 0.01). IL10 rs3024505 homozygous wildtype carriers were at 27% reduced risk of CRC per 10 g fibre per day (95% CI: 0.60-0.88) whereas variant carriers had no risk reduction by fibre intake. Also, interaction between IL10 C-592A and intake of fibre was found (P-value for interaction = 0.02). Among those eating <17.0 grams of fibre per day, carriers of an C-592A variant allele had a statistically significantly higher risk of colorectal cancer compared to homozygous wildtypes. No significant differences in colorectal cancer risk were observed between the reference group (CC and <17.0 g/day) and carriers of one C-592A variant allele eating 17.0 or more grams of dietary fibre per day. This suggests that the increased risk due to carrying the variant allele can be overcome by higher fibre intake. No interactions between IL10 polymorphisms and dietary meat, cereal, or fish intake, or between IL10 rs3024505 and smoking or NSAID use were found. Conclusions In this northern Caucasian cohort we found interaction between IL10 and dietary fibre in CRC carcinogenesis. High intake of fibre seems to protect against CRC among individuals with IL10 related genetic susceptibility to CRC. This finding should be evaluated in other prospective and population-based cohorts with different ethnic groups.
Collapse
|
654
|
Collins AJ, Schleicher TR, Rader BA, Nyholm SV. Understanding the role of host hemocytes in a squid/vibrio symbiosis using transcriptomics and proteomics. Front Immunol 2012; 3:91. [PMID: 22590467 PMCID: PMC3349304 DOI: 10.3389/fimmu.2012.00091] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2012] [Accepted: 04/08/2012] [Indexed: 11/13/2022] Open
Abstract
The symbiosis between the squid, Euprymna scolopes, and the bacterium, Vibrio fischeri, serves as a model for understanding interactions between beneficial bacteria and animal hosts. The establishment and maintenance of the association is highly specific and depends on the selection of V. fischeri and exclusion of non-symbiotic bacteria from the environment. Current evidence suggests that the host's cellular innate immune system, in the form of macrophage-like hemocytes, helps to mediate host tolerance of V. fischeri. To begin to understand the role of hemocytes in this association, we analyzed these cells by high-throughput 454 transcriptomic and liquid chromatography/tandem mass spectrometry (LC-MS/MS) proteomic analyses. 454 high-throughput sequencing produced 650, 686 reads totaling 279.9 Mb while LC-MS/MS analyses of circulating hemocytes putatively identified 702 unique proteins. Several receptors involved with the recognition of microbial-associated molecular patterns were identified. Among these was a complete open reading frame to a putative peptidoglycan recognition protein (EsPGRP5) with conserved residues for amidase activity. Assembly of the hemocyte transcriptome showed EsPGRP5 had high coverage, suggesting it is among the 5% most abundant transcripts in circulating hemocytes. Other transcripts and proteins identified included members of the conserved NF-κB signaling pathway, putative members of the complement pathway, the carbohydrate binding protein galectin, and cephalotoxin. Quantitative Real-Time PCR of complement-like genes, cephalotoxin, EsPGRP5, and a nitric oxide synthase showed differential expression in circulating hemocytes from adult squid with colonized light organs compared to those isolated from hosts where the symbionts were removed. These data suggest that the presence of the symbiont influences gene expression of the cellular innate immune system of E. scolopes.
Collapse
Affiliation(s)
- Andrew J Collins
- Department of Molecular and Cell Biology, University of Connecticut Storrs, CT, USA
| | | | | | | |
Collapse
|
655
|
Clemente JC, Ursell LK, Parfrey LW, Knight R. The impact of the gut microbiota on human health: an integrative view. Cell 2012; 148:1258-70. [PMID: 22424233 DOI: 10.1016/j.cell.2012.01.035] [Citation(s) in RCA: 2350] [Impact Index Per Article: 195.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Indexed: 11/24/2022]
Abstract
The human gut harbors diverse microbes that play a fundamental role in the well-being of their host. The constituents of the microbiota--bacteria, viruses, and eukaryotes--have been shown to interact with one another and with the host immune system in ways that influence the development of disease. We review these interactions and suggest that a holistic approach to studying the microbiota that goes beyond characterization of community composition and encompasses dynamic interactions between all components of the microbiota and host tissue over time will be crucial for building predictive models for diagnosis and treatment of diseases linked to imbalances in our microbiota.
Collapse
Affiliation(s)
- Jose C Clemente
- Department of Chemistry & Biochemistry, University of Colorado at Boulder, Boulder, CO 80309, USA
| | | | | | | |
Collapse
|
656
|
Sanchez LM, Wong WR, Riener RM, Schulze CJ, Linington RG. Examining the fish microbiome: vertebrate-derived bacteria as an environmental niche for the discovery of unique marine natural products. PLoS One 2012; 7:e35398. [PMID: 22574119 PMCID: PMC3344833 DOI: 10.1371/journal.pone.0035398] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Accepted: 03/16/2012] [Indexed: 01/11/2023] Open
Abstract
Historically, marine invertebrates have been a prolific source of unique natural products, with a diverse array of biological activities. Recent studies of invertebrate-associated microbial communities are revealing microorganisms as the true producers of many of these compounds. Inspired by the human microbiome project, which has highlighted the human intestine as a unique microenvironment in terms of microbial diversity, we elected to examine the bacterial communities of fish intestines (which we have termed the fish microbiome) as a new source of microbial and biosynthetic diversity for natural products discovery. To test the hypothesis that the fish microbiome contains microorganisms with unique capacity for biosynthesizing natural products, we examined six species of fish through a combination of dissection and culture-dependent evaluation of intestinal microbial communities. Using isolation media designed to enrich for marine Actinobacteria, we have found three main clades that show taxonomic divergence from known strains, several of which are previously uncultured. Extracts from these strains exhibit a wide range of activities against both Gram-positive and Gram-negative human pathogens, as well as several fish pathogens. Exploration of one of these extracts has identified the novel bioactive lipid sebastenoic acid as an anti-microbial agent, with activity against Staphylococcus aureus, Bacillus subtilis, Enterococcus faecium, and Vibrio mimicus.
Collapse
Affiliation(s)
- Laura M. Sanchez
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Weng Ruh Wong
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Romina M. Riener
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Christopher J. Schulze
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Roger G. Linington
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, California, United States of America
- * E-mail:
| |
Collapse
|
657
|
Abstract
The normally harmless behavior of bacteria in the intestinal tract is maintained by community structure and the integrity of host defenses. When either or both of these are compromised, a few disgruntled outcasts can cause a riot, taking down the whole neighborhood (pages 799-806).
Collapse
|
658
|
Dishaw LJ, Flores-Torres JA, Mueller MG, Karrer CR, Skapura DP, Melillo D, Zucchetti I, De Santis R, Pinto MR, Litman GW. A Basal chordate model for studies of gut microbial immune interactions. Front Immunol 2012; 3:96. [PMID: 22563328 PMCID: PMC3342567 DOI: 10.3389/fimmu.2012.00096] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Accepted: 04/12/2012] [Indexed: 12/23/2022] Open
Abstract
Complex symbiotic interactions at the surface of host epithelia govern most encounters between host and microbe. The epithelium of the gut is a physiologically ancient structure that is comprised of a single layer of cells and is thought to possess fully developed immunological capabilities. Ciona intestinalis (sea squirt), which is a descendant of the last common ancestor of all vertebrates, is a potentially valuable model for studying barrier defenses and gut microbial immune interactions. A variety of innate immunological phenomena have been well characterized in Ciona, of which many are active in the gut tissues. Interactions with gut microbiota likely involve surface epithelium, secreted immune molecules including variable region-containing chitin-binding proteins, and hemocytes from a densely populated laminar tissue space. The microbial composition of representative gut luminal contents has been characterized by molecular screening and a potentially relevant, reproducible, dysbiosis can be induced via starvation. The dialog between host and microbe in the gut can be investigated in Ciona against the background of a competent innate immune system and in the absence of the integral elements and processes that are characteristic of vertebrate adaptive immunity.
Collapse
Affiliation(s)
- Larry J Dishaw
- Department of Pediatrics, USF/ACH Children's Research Institute, University of South Florida College of Medicine St. Petersburg, FL, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
659
|
Konieczna P, Akdis CA, Quigley EMM, Shanahan F, O'Mahony L. Portrait of an immunoregulatory Bifidobacterium. Gut Microbes 2012; 3:261-6. [PMID: 22572827 PMCID: PMC3427218 DOI: 10.4161/gmic.20358] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
There is increasing interest in the administration of microbes or microbial metabolites for the prevention and treatment of aberrant inflammatory activity. The protective effects associated with these microbes are mediated by multiple mechanisms involving epithelial cells, DCs and T cells, but most data are derived from animal models. In this addendum, we summarize our recent data, showing that oral consumption of Bifidobacterium infantis 35624 is associated with enhanced IL-10 secretion and Foxp3 expression in human peripheral blood. In addition, we discuss the potential DC subset-specific mechanisms, which could contribute to DC(REG) and T(REG) programming by specific gut microbes.
Collapse
Affiliation(s)
- Patrycja Konieczna
- Swiss Institute of Allergy and Asthma Research; University of Zurich; Davos Platz, Switzerland
| | - Cezmi A. Akdis
- Swiss Institute of Allergy and Asthma Research; University of Zurich; Davos Platz, Switzerland
| | - Eamonn MM Quigley
- Alimentary Pharmabiotic Centre; University College Cork; National University of Ireland; Cork, Ireland
| | - Fergus Shanahan
- Alimentary Pharmabiotic Centre; University College Cork; National University of Ireland; Cork, Ireland
| | - Liam O'Mahony
- Swiss Institute of Allergy and Asthma Research; University of Zurich; Davos Platz, Switzerland,Correspondence to: Liam O'Mahony,
| |
Collapse
|
660
|
Brucker RM, Bordenstein SR. Speciation by symbiosis. Trends Ecol Evol 2012; 27:443-51. [PMID: 22541872 DOI: 10.1016/j.tree.2012.03.011] [Citation(s) in RCA: 238] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2011] [Revised: 03/27/2012] [Accepted: 03/28/2012] [Indexed: 01/21/2023]
Abstract
In the Origin of Species, Darwin struggled with how continuous changes within a species lead to the emergence of discrete species. Molecular analyses have since identified nuclear genes and organelles that underpin speciation. In this review, we explore the microbiota as a third genetic component that spurs species formation. We first recall Ivan Wallin's original conception from the early 20th century on the role that bacteria play in speciation. We then describe three fundamental observations that justify a prominent role for microbes in eukaryotic speciation, consolidate exemplar studies of microbe-assisted speciation and incorporate the microbiota into classic models of speciation.
Collapse
Affiliation(s)
- Robert M Brucker
- Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235, USA
| | | |
Collapse
|
661
|
Bucci V, Bradde S, Biroli G, Xavier JB. Social interaction, noise and antibiotic-mediated switches in the intestinal microbiota. PLoS Comput Biol 2012; 8:e1002497. [PMID: 22577356 PMCID: PMC3343147 DOI: 10.1371/journal.pcbi.1002497] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2011] [Accepted: 03/12/2012] [Indexed: 11/19/2022] Open
Abstract
The intestinal microbiota plays important roles in digestion and resistance against entero-pathogens. As with other ecosystems, its species composition is resilient against small disturbances but strong perturbations such as antibiotics can affect the consortium dramatically. Antibiotic cessation does not necessarily restore pre-treatment conditions and disturbed microbiota are often susceptible to pathogen invasion. Here we propose a mathematical model to explain how antibiotic-mediated switches in the microbiota composition can result from simple social interactions between antibiotic-tolerant and antibiotic-sensitive bacterial groups. We build a two-species (e.g. two functional-groups) model and identify regions of domination by antibiotic-sensitive or antibiotic-tolerant bacteria, as well as a region of multistability where domination by either group is possible. Using a new framework that we derived from statistical physics, we calculate the duration of each microbiota composition state. This is shown to depend on the balance between random fluctuations in the bacterial densities and the strength of microbial interactions. The singular value decomposition of recent metagenomic data confirms our assumption of grouping microbes as antibiotic-tolerant or antibiotic-sensitive in response to a single antibiotic. Our methodology can be extended to multiple bacterial groups and thus it provides an ecological formalism to help interpret the present surge in microbiome data.
Collapse
Affiliation(s)
- Vanni Bucci
- Program in Computational Biology, Memorial Sloan-Kettering Cancer Center, New York, New York, United States of America
- * E-mail: (VB); (SB); (JBX)
| | - Serena Bradde
- Program in Computational Biology, Memorial Sloan-Kettering Cancer Center, New York, New York, United States of America
- * E-mail: (VB); (SB); (JBX)
| | - Giulio Biroli
- Institut Physique Théorique (IPhT) CEA Saclay, and CNRS URA, Gif Sur Yvette, France
| | - Joao B. Xavier
- Program in Computational Biology, Memorial Sloan-Kettering Cancer Center, New York, New York, United States of America
- * E-mail: (VB); (SB); (JBX)
| |
Collapse
|
662
|
Gomez A, Luckey D, Yeoman CJ, Marietta EV, Berg Miller ME, Murray JA, White BA, Taneja V. Loss of sex and age driven differences in the gut microbiome characterize arthritis-susceptible 0401 mice but not arthritis-resistant 0402 mice. PLoS One 2012; 7:e36095. [PMID: 22553482 PMCID: PMC3338357 DOI: 10.1371/journal.pone.0036095] [Citation(s) in RCA: 169] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Accepted: 03/27/2012] [Indexed: 11/24/2022] Open
Abstract
Background HLA-DRB1*0401 is associated with susceptibility, while HLA-DRB1*0402 is associated with resistance to developing rheumatoid arthritis (RA) and collagen-induced arthritis in humans and transgenic mice respectively. The influence of gut-joint axis has been suggested in RA, though not yet proven. Methodology/Principal Findings We have used HLA transgenic mice carrying arthritis susceptible and -resistant HLA-DR genes to explore if genetic factors and their interaction with gut flora gut can be used to predict susceptibility to develop arthritis. Pyrosequencing of the 16S rRNA gene from the fecal microbiomes of DRB1*0401 and DRB1*0402 transgenic mice revealed that the guts of *0401 mice is dominated by a Clostridium-like bacterium, whereas the guts of *0402 mice are enriched for members of the Porphyromonadaceae family and Bifidobacteria. DRB1*0402 mice harbor a dynamic sex and age-influenced gut microbiome while DRB1*0401 mice did not show age and sex differences in gut microbiome even though they had altered gut permeability. Cytokine transcripts, measured by rtPCR, in jejuna showed differential TH17 regulatory network gene transcripts in *0401 and *0402 mice. Conclusions/Significance We have demonstrated for the first time that HLA genes in association with the gut microbiome may determine the immune environment and that the gut microbiome might be a potential biomarker as well as contributor for susceptibility to arthritis. Identification of pathogenic commensal bacteria would provide new understanding of disease pathogenesis, thereby leading to novel approaches for therapy.
Collapse
Affiliation(s)
- Andres Gomez
- Institute for Genomic Biology, University of Illinois, Urbana, Illinois, United States of America
| | - David Luckey
- Department of Immunology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Carl J. Yeoman
- Institute for Genomic Biology, University of Illinois, Urbana, Illinois, United States of America
| | - Eric V. Marietta
- Department of Gasteroenterology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Margret E. Berg Miller
- Institute for Genomic Biology, University of Illinois, Urbana, Illinois, United States of America
| | - Joseph A. Murray
- Department of Immunology, Mayo Clinic, Rochester, Minnesota, United States of America
- Department of Gasteroenterology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Bryan A. White
- Institute for Genomic Biology, University of Illinois, Urbana, Illinois, United States of America
- Department of Animal Sciences, University of Illinois, Urbana, Illinois, United States of America
- * E-mail: (BAW); (VT)
| | - Veena Taneja
- Department of Immunology, Mayo Clinic, Rochester, Minnesota, United States of America
- Department of Rheumatology, Mayo Clinic, Rochester, Minnesota, United States of America
- * E-mail: (BAW); (VT)
| |
Collapse
|
663
|
Kelly D, Delday MI, Mulder I. Microbes and microbial effector molecules in treatment of inflammatory disorders. Immunol Rev 2012; 245:27-44. [PMID: 22168412 DOI: 10.1111/j.1600-065x.2011.01079.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The healthy gut tolerates very large numbers of diverse bacterial species belonging mainly to the Bacteroidetes and Firmicutes phyla. These bacteria normally coexist peacefully with the gut and help maintain immune homeostasis and tolerance. The mechanisms promoting tolerance affect various cell populations, including the epithelial cells lining the gut, resident dendritic cells (DCs), and gut-homing T cells. Gut bacteria also influence multiple signaling pathways from Toll-like receptors to nuclear factor κB and regulate the functionality of DCs and T cells. Several bacterial species have been identified that promote T-cell differentiation, in particular T-helper 17 and T-regulatory cells. Insight into the molecular mechanisms by which bacteria mediate these effects will be very important in identifying new ways of treating intestinal and extra-intestinal immune-mediated diseases. These diseases are increasing dramatically in the human population and require new treatments. It may be possible in the future to identify specific bacterial species or strains that can correct for T-cell imbalances in the gut and promote immune homeostasis, both locally and systemically. In addition, new information describing microbial genomes affords the opportunity to mine for functional genes that may lead to new generation drugs relevant to a range of inflammatory disease conditions.
Collapse
Affiliation(s)
- Denise Kelly
- Gut Immunology Group, Rowett Institute of Nutrition and Health, University of Aberdeen, Aberdeen, UK.
| | | | | |
Collapse
|
664
|
Fagundes CT, Amaral FA, Teixeira AL, Souza DG, Teixeira MM. Adapting to environmental stresses: the role of the microbiota in controlling innate immunity and behavioral responses. Immunol Rev 2012; 245:250-64. [PMID: 22168425 DOI: 10.1111/j.1600-065x.2011.01077.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Mammals are subject to colonization by an astronomical number of mutualistic and commensal microorganisms on their environmental exposed surfaces. These mutualistic species build up a complex community, called the indigenous microbiota, which aid their hosts in several physiological activities. In this review, we show that the transition between a non-colonized and a colonized state is associated with modification on the pattern of host inflammatory and behavioral responsiveness. There is a shift from innate anti-inflammatory cytokine production to efficient release of proinflammatory mediators and rapid mobilization of leukocytes upon infection or other stimuli. In addition, host responses to hypernociceptive and stressful stimuli are modulated by indigenous microbiota, partly due to the altered pattern of innate and acquired immune responsiveness of the non-colonized host. These altered responses ultimately lead to significant alteration in host behavior to environmental threats. Therefore, host colonization by indigenous microbiota modifies the way the host perceives and reacts to environmental stimuli, improving resilience of the entire host-microorganism consortium to environmental stresses.
Collapse
Affiliation(s)
- Caio T Fagundes
- Immunopharmacology, Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | | | | | | | | |
Collapse
|
665
|
Mathis D, Benoist C. The influence of the microbiota on type-1 diabetes: on the threshold of a leap forward in our understanding. Immunol Rev 2012; 245:239-49. [PMID: 22168424 DOI: 10.1111/j.1600-065x.2011.01084.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The last several years have seen breakthroughs in techniques to track the symbiont communities that normally colonize mammals (the microbiota) and in cataloguing the universe of the genes they carry (the microbiome). Applying these methods to human patients and corresponding murine models should allow us to decipher just how the microbiota impacts type-1 diabetes, i.e. which particular microbes are responsible and the cellular and molecular processes that are involved. Here, at its threshold, we set the stage for what promises to be an exciting rejuvenated area of investigation.
Collapse
Affiliation(s)
- Diane Mathis
- Division of Immunology, Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115, USA
| | | |
Collapse
|
666
|
Abstract
PURPOSE OF REVIEW This review focuses on recent research that explores the role of infectious organisms in the development of autoimmunity and rheumatoid arthritis (RA). RECENT FINDINGS Human and animal studies provide further evidence supporting a role for the periodontal pathogen, Porphyromonas gingivalis, in the development of RA. The microbiome plays a key role in the developing immune system. Alterations in the bowel microbiome lead to altered innate and adaptive immune responses potentially relevant to the development or persistence of RA. SUMMARY Microbes and the host response to microbes are important factors in the maintenance of health. Abnormalities or imbalances in these responses can lead to the development of autoimmune inflammatory conditions such as RA.
Collapse
|
667
|
Virta L, Auvinen A, Helenius H, Huovinen P, Kolho KL. Association of repeated exposure to antibiotics with the development of pediatric Crohn's disease--a nationwide, register-based finnish case-control study. Am J Epidemiol 2012; 175:775-84. [PMID: 22366379 DOI: 10.1093/aje/kwr400] [Citation(s) in RCA: 127] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
To determine whether childhood exposure to antibiotics is associated with the risk of developing inflammatory bowel disease (IBD), the authors conducted a national, register-based study comprising all children born in 1994-2008 in Finland and diagnosed with IBD by October 2010. The authors identified 595 children with IBD (233 with Crohn's disease and 362 with ulcerative colitis) and 2,380 controls matched for age, gender, and place of residence. The risk of pediatric Crohn's disease increased with the number of antibiotic purchases from birth to the index date and persisted when the 6 months preceding the case's diagnosis were excluded (for 7-10 purchases vs. none, odds ratio = 3.48, 95% confidence interval: 1.57, 7.34; conditional logistic regression). The association between Crohn's disease and antibiotic use was stronger in boys than in girls (P = 0.01). Cephalosporins showed the strongest association with Crohn's disease (for 3 purchases vs. nonuse, odds ratio = 2.82, 95% confidence interval: 1.65, 4.81). Antibiotic exposure was not associated with the development of pediatric ulcerative colitis. Repeated use of antibiotics may reflect shared susceptibility to childhood infections and pediatric Crohn's disease or alternatively may trigger disease development.
Collapse
Affiliation(s)
- Lauri Virta
- Children’s Hospital, University of Helsinki, Box 281, FIN-00029 Helsinki, Finland.
| | | | | | | | | |
Collapse
|
668
|
Affiliation(s)
- Bastiaan Star
- Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biology, University of Oslo, Oslo, Norway.
| | | |
Collapse
|
669
|
Jongwattanapisan P, Suntornsaratoon P, Wongdee K, Dorkkam N, Krishnamra N, Charoenphandhu N. Impaired body calcium metabolism with low bone density and compensatory colonic calcium absorption in cecectomized rats. Am J Physiol Endocrinol Metab 2012; 302:E852-63. [PMID: 22275757 DOI: 10.1152/ajpendo.00503.2011] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
An earlier study reported that cecal calcium absorption contributes less than 10% of total calcium absorbed by the intestine, although the cecum has the highest calcium transport rate compared with other intestinal segments. Thus, the physiological significance of the cecum pertaining to body calcium metabolism remains elusive. Herein, a 4-wk calcium balance study in cecectomized rats revealed an increase in fecal calcium loss with marked decreases in fractional calcium absorption and urinary calcium excretion only in the early days post-operation, suggesting the presence of a compensatory mechanism to minimize intestinal calcium wasting. Further investigation in cecectomized rats showed that active calcium transport was enhanced in the proximal colon but not in the small intestine, whereas passive calcium transport along the whole intestine was unaltered. Since apical exposure to calcium-sensing receptor (CaSR) agonists similarly increased proximal colonic calcium transport, activation of apical CaSR in colonic epithelial cells could have been involved in this hyperabsorption. Calcium transporter genes, i.e., TRPV6 and calbindin-D(9k), were also upregulated in proximal colonic epithelial cells. Surprisingly, elevated serum parathyroid hormone levels and hyperphosphatemia were evident in cecectomized rats despite normal plasma calcium levels, suggesting that colonic compensation alone might be insufficient to maintain normocalcemia. Thus, massive bone loss occurred in both cortical and trabecular sites, including lumbar vertebrae, femora, and tibiae. The presence of compensatory colonic calcium hyperabsorption with pervasive osteopenia in cecectomized rats therefore corroborates that the cecum is extremely crucial for body calcium homeostasis.
Collapse
|
670
|
Frei R, Lauener RP, Crameri R, O'Mahony L. Microbiota and dietary interactions: an update to the hygiene hypothesis? Allergy 2012; 67:451-61. [PMID: 22257145 DOI: 10.1111/j.1398-9995.2011.02783.x] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/12/2011] [Indexed: 12/31/2022]
Abstract
The dramatic increase in the incidence and severity of allergy and asthma has been proposed to be linked with an altered exposure to, and colonization by, micro-organisms, particularly early in life. However, other lifestyle factors such as diet and physical activity are also thought to be important, and it is likely that multiple environmental factors with currently unrecognized interactions contribute to the atopic state. This review will focus on the potential role of microbial metabolites in immunoregulatory functions and highlights the known molecular mechanisms, which may mediate the interactions between diet, microbiota, and protection from allergy and asthma.
Collapse
Affiliation(s)
| | | | - R. Crameri
- Swiss Institute of Allergy and Asthma Research; University of Zurich; Davos; Switzerland
| | - L. O'Mahony
- Swiss Institute of Allergy and Asthma Research; University of Zurich; Davos; Switzerland
| |
Collapse
|
671
|
de Koning HD, Simon A, Zeeuwen PLJM, Schalkwijk J. Pattern recognition receptors in infectious skin diseases. Microbes Infect 2012; 14:881-93. [PMID: 22516809 DOI: 10.1016/j.micinf.2012.03.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Revised: 03/15/2012] [Accepted: 03/16/2012] [Indexed: 12/27/2022]
Abstract
During the last decade, multiple pattern recognition receptors (PRRs) have been identified. These are involved in the innate immune response against a plethora of pathogens. However, PRR functioning can also be detrimental, even during infections. This review discusses the current knowledge on PRRs that recognize dermatotropic pathogens, and potential therapeutical implications.
Collapse
Affiliation(s)
- Heleen D de Koning
- Department of Dermatology, Radboud University Nijmegen Medical Centre, PO Box 9101, 6500 HB, The Netherlands.
| | | | | | | |
Collapse
|
672
|
Boudreau MA, Fisher JF, Mobashery S. Messenger functions of the bacterial cell wall-derived muropeptides. Biochemistry 2012; 51:2974-90. [PMID: 22409164 DOI: 10.1021/bi300174x] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Bacterial muropeptides are soluble peptidoglycan structures central to recycling of the bacterial cell wall and messengers in diverse cell signaling events. Bacteria sense muropeptides as signals that antibiotics targeting cell-wall biosynthesis are present, and eukaryotes detect muropeptides during the innate immune response to bacterial infection. This review summarizes the roles of bacterial muropeptides as messengers, with a special emphasis on bacterial muropeptide structures and the relationship of structure to the biochemical events that the muropeptides elicit. Muropeptide sensing and recycling in both Gram-positive and Gram-negative bacteria are discussed, followed by muropeptide sensing by eukaryotes as a crucial event in the innate immune response of insects (via peptidoglycan-recognition proteins) and mammals (through Nod-like receptors) to bacterial invasion.
Collapse
Affiliation(s)
- Marc A Boudreau
- Department of Chemistry and Biochemistry, Nieuwland Science Hall, University of Notre Dame, Notre Dame, Indiana 46556, USA
| | | | | |
Collapse
|
673
|
Acevedo N, Sánchez J, Zakzuk J, Bornacelly A, Quiróz C, Alvarez Á, Puello M, Mendoza K, Martínez D, Mercado D, Jiménez S, Caraballo L. Particular characteristics of allergic symptoms in tropical environments: follow up to 24 months in the FRAAT birth cohort study. BMC Pulm Med 2012; 12:13. [PMID: 22439773 PMCID: PMC3331807 DOI: 10.1186/1471-2466-12-13] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2011] [Accepted: 03/22/2012] [Indexed: 12/03/2022] Open
Abstract
Background Early wheezing and asthma are relevant health problems in the tropics. Mite sensitization is an important risk factor, but the roles of others, inherent in poverty, are unknown. We designed a birth-cohort study in Cartagena (Colombia) to investigate genetic and environmental risk factors for asthma and atopy, considering as particular features perennial exposure to mites, parasite infections and poor living conditions. Methods Pregnant women representative of the low-income suburbs of the city were randomly screened for eligibility at delivery; 326 mother-infant pairs were included at baseline and biological samples were collected from birth to 24 months for immunological testing, molecular genetics and gene expression analysis. Pre and post-natal information was collected using questionnaires. Results 94% of families were from the poorest communes of the city, 40% lacked sewage and 11% tap-water. Intestinal parasites were found as early as 3 months; by the second year, 37.9% of children have had parasites and 5.22% detectable eggs of Ascaris lumbricoides in stools (Median 3458 epg, IQR 975-9256). The prevalence of "wheezing ever" was 17.5% at 6 months, 31.1% at 12 months and 38.3% at 24 months; and recurrent wheezing (3 or more episodes) 7.1% at 12 months and 14.2% at 24 months. Maternal rhinitis [aOR 3.03 (95%CI 1.60-5.74), p = 0.001] and male gender [aOR 2.09 (95%CI 1.09 - 4.01), p = 0.026], increased risk for wheezing at 6 months. At 24 months, maternal asthma was the main predisposing factor for wheezing [aOR 3.65 (95%CI 1.23-10.8), p = 0.01]. Clinical symptoms of milk/egg allergy or other food-induced allergies were scarce (1.8%) and no case of atopic eczema was observed. Conclusions Wheezing is the most frequent phenotype during the first 24 months of life and is strongly associated with maternal asthma. At 24 months, the natural history of allergic symptoms is different to the "atopic march" described in some industrialized countries. This cohort is representative of socially deprived urban areas of underdeveloped tropical countries. The collection of biological samples, data on exposure and defined phenotypes, will contribute to understand the gene/environment interactions leading to allergy inception and evolution.
Collapse
Affiliation(s)
- Nathalie Acevedo
- Institute for Immunological Research, University of Cartagena, Cartagena, Colombia
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
674
|
Rodrigues DM, Sousa AJ, Johnson-Henry KC, Sherman PM, Gareau MG. Probiotics are effective for the prevention and treatment of Citrobacter rodentium-induced colitis in mice. J Infect Dis 2012; 206:99-109. [PMID: 22430833 DOI: 10.1093/infdis/jis177] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Probiotics prevent disease induced by Citrobacter rodentium, a murine-specific enteric pathogen. Whether probiotics can be used to interrupt the infectious process following initiation of infection was determined. METHODS C57BL/6 adult and neonatal mice were challenged with C. rodentium, and a probiotic mixture containing Lactobacillus helveticus and Lactobacillus rhamnosus was provided 1 week before bacterial challenge, concurrently with infection, or 3 days and 6 days after infection. Mice were sacrificed 10 days after infection, and disease severity was assessed by histological analysis and in vivo intestinal permeability assay. Inflammatory pathways and the composition of the fecal microbiome were assessed in adult mice. RESULTS Preadministration and coadministration of probiotics ameliorated C. rodentium-induced barrier dysfunction, epithelial hyperplasia, and binding of the pathogen to host colonocytes in adults, with similar findings in neonatal mice. Upregulated tumor necrosis factor α and interferon γ transcripts were suppressed in the pretreated probiotic group, whereas interleukin 17 transcription was suppressed with probiotics given up to 3 days after infection. Probiotics promoted transcription of interleukin 10 and FOXP3, and increased follicular T-regulatory cells in pretreatment mice. C. rodentium infection resulted in an altered fecal microbiome, which was normalized with probiotic intervention. CONCLUSIONS This study provides evidence that probiotics can prevent illness and treat disease in an animal model of infectious colitis.
Collapse
Affiliation(s)
- David M Rodrigues
- Research Institute, Hospital for Sick Children, University of Toronto, Canada
| | | | | | | | | |
Collapse
|
675
|
Induction of intestinal pro-inflammatory immune responses by lipoteichoic acid. JOURNAL OF INFLAMMATION-LONDON 2012; 9:7. [PMID: 22423982 PMCID: PMC3325164 DOI: 10.1186/1476-9255-9-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Accepted: 03/16/2012] [Indexed: 02/02/2023]
Abstract
Background The cellular and molecular mechanisms of inflammatory bowel disease are not fully understood; however, data indicate that uncontrolled chronic inflammation induced by bacterial gene products, including lipoteichoic acid (LTA), may trigger colonic inflammation resulting in disease pathogenesis. LTA is a constituent glycolipid of Gram-positive bacteria that shares many inflammatory properties with lipopolysaccharide and plays a critical role in the pathogenesis of severe inflammatory responses via Toll-like receptor 2. Accordingly, we elucidate the role of LTA in immune stimulation and induced colitis in vivo. Methods To better understand the molecular mechanisms utilized by the intestinal microbiota and their gene products to induce or subvert inflammation, specifically the effect(s) of altered surface layer protein expression on the LTA-mediated pro-inflammatory response, the Lactobacillus acidophilus surface layer protein (Slp) genes encoding SlpB and SlpX were deleted resulting in a SlpB- and SlpX- mutant that continued to express SlpA (assigned as NCK2031). Results Our data show profound activation of dendritic cells by NCK2031, wild-type L. acidophilus (NCK56), and purified Staphylococcus aureus-LTA. In contrary to the LTA-deficient strain NCK2025, the LTA-expressing strains NCK2031 and NCK56, as well as S. aureus-LTA, induce pro-inflammatory innate and T cell immune responses in vivo. Additionally, neither NCK2031 nor S. aureus-LTA supplemented in drinking water protected mice from DSS-colitis, but instead, induced significant intestinal inflammation resulting in severe colitis and tissue destruction. Conclusions These findings suggest that directed alteration of two of the L. acidophilus NCFM-Slps did not ameliorate LTA-induced pro-inflammatory signals and subsequent colitis.
Collapse
|
676
|
Dishaw LJ, Haire RN, Litman GW. The amphioxus genome provides unique insight into the evolution of immunity. Brief Funct Genomics 2012; 11:167-76. [PMID: 22402506 DOI: 10.1093/bfgp/els007] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Immune systems evolve as essential strategies to maintain homeostasis with the environment, prevent microbial assault and recycle damaged host tissues. The immune system is composed of two components, innate and adaptive immunity. The former is common to all animals while the latter consists of a vertebrate-specific system that relies on somatically derived lymphocytes and is associated with near limitless genetic diversity as well as long-term memory. Deuterostome invertebrates provide a view of immune repertoires in phyla that immediately predate the origins of vertebrates. Genomic studies in amphioxus, a cephalochordate, have revealed homologs of genes encoding most innate immune receptors found in vertebrates; however, many of the gene families have undergone dramatic expansions, greatly increasing the innate immune repertoire. In addition, domain-swapping accounts for the innovation of new predicted pathways of receptor function. In both amphioxus and Ciona, a urochordate, the VCBPs (variable region containing chitin-binding proteins), which consist of immunoglobulin V (variable) and chitin binding domains, mediate recognition through the V domains. The V domains of VCBPs in amphioxus exhibit high levels of allelic complexity that presumably relate to functional specificity. Various features of the amphioxus immune repertoire reflect novel selective pressures, which likely have resulted in innovative strategies. Functional genomic studies underscore the value of amphioxus as a model for studying innate immunity and may help reveal how unique relationships between innate immune receptors and both pathogens and symbionts factored in the evolution of adaptive immune systems.
Collapse
Affiliation(s)
- Larry J Dishaw
- Department of Pediatrics, University of South Florida, Children's Research Institute, USA
| | | | | |
Collapse
|
677
|
Mohamadzadeh M, Owen JL. Reprogramming intestinal immunity is the answer to induced pathogenic inflammation. Immunotherapy 2012; 3:1415-7. [PMID: 22091675 DOI: 10.2217/imt.11.140] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
|
678
|
Arrieta MC, Finlay BB. The commensal microbiota drives immune homeostasis. Front Immunol 2012; 3:33. [PMID: 22566917 PMCID: PMC3341987 DOI: 10.3389/fimmu.2012.00033] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2011] [Accepted: 02/14/2012] [Indexed: 12/15/2022] Open
Abstract
For millions of years, microbes have coexisted with eukaryotic cells at the mucosal surfaces of vertebrates in a complex, yet usually harmonious symbiosis. An ever-expanding number of reports describe how eliminating or shifting the intestinal microbiota has profound effects on the development and functionality of the mucosal and systemic immune systems. Here, we examine some of the mechanisms by which bacterial signals affect immune homeostasis. Focusing on the strategies that microbes use to keep our immune system healthy, as opposed to trying to correct the immune imbalances caused by dysbiosis, may prove to be a more astute and efficient way of treating immune-mediated disease.
Collapse
Affiliation(s)
- Marie-Claire Arrieta
- Michael Smith Laboratories, University of British Columbia Vancouver, BC, Canada
| | | |
Collapse
|
679
|
Incoming pathogens team up with harmless 'resident' bacteria. Trends Microbiol 2012; 20:160-4. [PMID: 22390987 DOI: 10.1016/j.tim.2012.02.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2011] [Revised: 01/31/2012] [Accepted: 02/06/2012] [Indexed: 02/03/2023]
Abstract
Microbial diseases occur as a result of multifarious host-pathogen interactions. However, invading pathogens encounter a large number of different harmless and beneficial bacterial species, which colonize and reside in the host. Surprisingly, there has been little study of the possible interactions between incoming pathogens and the resident bacterial community. Recent studies have revealed that resident bacteria assist different types of incoming pathogens via a wide variety of mechanisms including cell-cell signaling, metabolic interactions, evasion of the immune response and a resident-to-pathogen switch. This calls for serious consideration of pathogen-microbe interactions in the host with respect to disease severity and progression.
Collapse
|
680
|
Willermain F, Rosenbaum JT, Bodaghi B, Rosenzweig HL, Childers S, Behrend T, Wildner G, Dick AD. Interplay between innate and adaptive immunity in the development of non-infectious uveitis. Prog Retin Eye Res 2012; 31:182-94. [PMID: 22120610 PMCID: PMC3288447 DOI: 10.1016/j.preteyeres.2011.11.004] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2011] [Revised: 11/10/2011] [Accepted: 11/11/2011] [Indexed: 12/14/2022]
Abstract
In vertebrates, the innate and adaptive immune systems have evolved seamlessly to protect the host by rapidly responding to danger signals, eliminating pathogens and creating immunological memory as well as immunological tolerance to self. The innate immune system harnesses receptors that recognize conserved pathogen patterns and alongside the more specific recognition systems and memory of adaptive immunity, their interplay is evidenced by respective roles during generation and regulation of immune responses. The hallmark of adaptive immunity which requires engagement of innate immunity is an ability to discriminate between self and non-self (and eventually between pathogen and symbiont) as well as peripheral control mechanisms maintaining immunological health and appropriate responses. Loss of control mechanisms and/or regulation of either the adaptive or the innate immune system lead to autoimmunity and autoinflammation respectively. Although autoimmune pathways have been largely studied to date in the context of development of non-infectious intraocular inflammation, the recruitment and activation of innate immunity is required for full expression of the varied phenotypes of non-infectious uveitis. Since autoimmunity and autoinflammation implicate different molecular pathways, even though some convergence occurs, increasing our understanding of their respective roles in the development of uveitis will highlight treatment targets and influence our understanding of immune mechanisms operative in other retinal diseases. Herein, we extrapolate from the basic mechanisms of activation and control of innate and adaptive immunity to how autoinflammatory and autoimmune pathways contribute to disease development in non-infectious uveitis patients.
Collapse
Affiliation(s)
- François Willermain
- Department of Ophthalmology, CHU St-Pierre and Brugmann, Université Libre de Bruxelles, Belgium.
| | | | | | | | | | | | | | | |
Collapse
|
681
|
Theilacker C, Kropec A, Hammer F, Sava I, Wobser D, Sakinc T, Codée JDC, Hogendorf WFJ, van der Marel GA, Huebner J. Protection against Staphylococcus aureus by antibody to the polyglycerolphosphate backbone of heterologous lipoteichoic acid. J Infect Dis 2012; 205:1076-85. [PMID: 22362863 DOI: 10.1093/infdis/jis022] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Type 1 lipoteichoic acid (LTA) is present in many clinically important gram-positive bacteria, including enterococci, streptococci, and staphylococci, and antibodies against LTA have been shown to opsonize nonencapsulated Enterococcus faecalis strains. In the present study, we show that antibodies against E. faecalis LTA also bind to type 1 LTA from other gram-positive species and opsonized Staphylocccus epidermidis and Staphylcoccus aureus strains as well as group B streptococci. Inhibition studies using teichoic acid oligomers indicated that cross-reactive opsonic antibodies bind to the teichoic acid backbone. Passive immunization with rabbit antibodies against E. faecalis LTA promoted the clearance of bacteremia by E. faecalis and S. epidermidis in mice. Furthermore, passive protection also reduced mortality in a murine S. aureus peritonitis model. The effectiveness of rabbit antibody against LTA suggests that this conserved bacterial structure could function as a single vaccine antigen that targets multiple gram-positive pathogens.
Collapse
Affiliation(s)
- Christian Theilacker
- Center for Chronic Immunodeficiency, University Medical Center Freiburg and University of Freiburg, Freiburg, Germany.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
682
|
Abstract
As in mammals, insect health is strongly influenced by the composition and activities of resident microorganisms. However, the microbiota of insects is generally less diverse than that of mammals, allowing microbial function in insects to be coupled to individual, identified microbial species. This trait of insect symbioses facilitates our understanding of the mechanisms that promote insect-microbial coexistence and the processes by which the microbiota affect insect well-being. As a result, insects are potentially ideal models to study various aspects of interactions between the host and its resident microorganisms that would be impractical or unfeasible in mammals and to generate hypotheses for subsequent testing in mammalian models.
Collapse
Affiliation(s)
- Angela E Douglas
- Department of Entomology, Comstock Hall, Cornell University, Ithaca, NY 14853, USA.
| |
Collapse
|
683
|
de St Groth BF. Regulatory T-cell abnormalities and the global epidemic of immuno-inflammatory disease. Immunol Cell Biol 2012; 90:256-9. [PMID: 22310378 DOI: 10.1038/icb.2011.113] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The incidence of autoimmune, allergic and inflammatory disease is increasing due to as yet unidentified environmental factors related to western living conditions. Here, I propose that alterations in the gut microbiome, acting via regulatory T cells (Tregs), may be responsible for this epidemic. Tregs control the threshold for peripheral antigen recognition via tonic downregulation of dendritic cell (DC) costimulation, and are also implicated in maintaining the tolerogenic function of DCs. In this model, minor perturbations in Treg number or function are predicted to lower the activation threshold, allowing proliferation and differentiation of self-reactive CD4T cells of too low an affinity to have undergone negative selection in the thymus. Failure to maintain the tolerogenic commitment of DCs exposed to commensal microbes and allergens could result in potentially pathogenic, allergic and inflammatory responses at epithelial surfaces.
Collapse
Affiliation(s)
- Barbara Fazekas de St Groth
- Centenary Institute of Cancer Medicine and Cell Biology, Discipline of Dermatology, University of Sydney, Newtown, New South Wales, Australia.
| |
Collapse
|
684
|
Establishment of characteristic gut bacteria during development of the honeybee worker. Appl Environ Microbiol 2012; 78:2830-40. [PMID: 22307297 DOI: 10.1128/aem.07810-11] [Citation(s) in RCA: 352] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Previous surveys have shown that adult honeybee (Apis mellifera) workers harbor a characteristic gut microbiota that may play a significant role in bee health. For three major phylotypes within this microbiota, we have characterized distributions and abundances across the life cycle and among gut organs. These distinctive phylotypes, called Beta, Firm-5, and Gamma-1 (BFG), were assayed using quantitative PCR, fluorescent in situ hybridization (FISH) microscopy, and the experimental manipulation of inoculation routes within developing bees. Adult workers (9 to 30 days posteclosion) contained a large BFG microbiota with a characteristic distribution among gut organs. The crop and midgut were nearly devoid of these phylotypes, while the ileum and rectum together contained more than 95% of the total BFG microbiota. The ileum contained a stratified community in which the Beta and Gamma-1 phylotypes dominated, filling the longitudinal folds of this organ. Deep sequencing of 16S rRNA genes showed clear differences among communities in midgut, ileum, and rectum. In contrast with older workers, larvae and newly emerged workers contain few or no bacteria, and their major food source, bee bread, lacks most characteristic phylotypes. In experiments aimed at determining the route of inoculation, newly emerged workers (NEWs) sometimes acquired the typical phylotypes through contact with older workers, contact with the hive, and emergence from the brood cell; however, transmission was patchy in these assays. Our results outline a colonization pattern for the characteristic phylotypes through A. mellifera ontogeny. We propose the names "Candidatus Snodgrassella alvi" and "Candidatus Gilliamella apicola" for the Beta and Gamma-1 phylotypes, respectively.
Collapse
|
685
|
Szafranski-Schneider E, Swidergall M, Cottier F, Tielker D, Román E, Pla J, Ernst JF. Msb2 shedding protects Candida albicans against antimicrobial peptides. PLoS Pathog 2012; 8:e1002501. [PMID: 22319443 PMCID: PMC3271078 DOI: 10.1371/journal.ppat.1002501] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2011] [Accepted: 12/09/2011] [Indexed: 11/30/2022] Open
Abstract
Msb2 is a sensor protein in the plasma membrane of fungi. In the human fungal pathogen C. albicans Msb2 signals via the Cek1 MAP kinase pathway to maintain cell wall integrity and allow filamentous growth. Msb2 doubly epitope-tagged in its large extracellular and small cytoplasmic domain was efficiently cleaved during liquid and surface growth and the extracellular domain was almost quantitatively released into the growth medium. Msb2 cleavage was independent of proteases Sap9, Sap10 and Kex2. Secreted Msb2 was highly O-glycosylated by protein mannosyltransferases including Pmt1 resulting in an apparent molecular mass of >400 kDa. Deletion analyses revealed that the transmembrane region is required for Msb2 function, while the large N-terminal and the small cytoplasmic region function to downregulate Msb2 signaling or, respectively, allow its induction by tunicamycin. Purified extracellular Msb2 domain protected fungal and bacterial cells effectively from antimicrobial peptides (AMPs) histatin-5 and LL-37. AMP inactivation was not due to degradation but depended on the quantity and length of the Msb2 glycofragment. C. albicans msb2 mutants were supersensitive to LL-37 but not histatin-5, suggesting that secreted rather than cell-associated Msb2 determines AMP protection. Thus, in addition to its sensor function Msb2 has a second activity because shedding of its glycofragment generates AMP quorum resistance. Microbial pathogens are attacked by antimicrobial peptides (AMPs) produced by the human host. AMPs kill pathogens and recruit immune cells to the site of infection. In defense, the human fungal pathogen Candida albicans continuously cleaves and secretes a glycoprotein fragment of the surface protein Msb2, which protects against AMPs. The results suggest that shed Msb2 allows fungal colonies to persist and avoid inflammatory responses caused by AMPs. Msb2 shedding and its additional role in stabilizing the fungal cell wall may be considered as novel diagnostic tools and targets for antifungal action.
Collapse
Affiliation(s)
| | - Marc Swidergall
- Department Biologie, Molekulare Mykologie, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Fabien Cottier
- Department Biologie, Molekulare Mykologie, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Denis Tielker
- Department Biologie, Molekulare Mykologie, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Elvira Román
- Departamento de Microbiología II, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
| | - Jesus Pla
- Departamento de Microbiología II, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
| | - Joachim F. Ernst
- Department Biologie, Molekulare Mykologie, Heinrich-Heine-Universität, Düsseldorf, Germany
- * E-mail:
| |
Collapse
|
686
|
Kirkland D, Benson A, Mirpuri J, Pifer R, Hou B, DeFranco AL, Yarovinsky F. B cell-intrinsic MyD88 signaling prevents the lethal dissemination of commensal bacteria during colonic damage. Immunity 2012; 36:228-38. [PMID: 22306056 DOI: 10.1016/j.immuni.2011.11.019] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Revised: 10/24/2011] [Accepted: 11/30/2011] [Indexed: 12/12/2022]
Abstract
The Toll-like receptor adaptor protein MyD88 is essential for the regulation of intestinal homeostasis in mammals. In this study, we determined that Myd88-deficient mice are susceptible to colonic damage that is induced by dextran sulfate sodium (DSS) administration resulting from uncontrolled dissemination of intestinal commensal bacteria. The DSS-induced mortality of Myd88-deficient mice was completely prevented by antibiotic treatment to deplete commensal bacteria. By using cell type-specific Myd88-deficient mice, we established that B cell-intrinsic MyD88 signaling plays a central role in the resistance to DSS-induced colonic damage via the production of IgM and complement-mediated control of intestinal bacteria. Our results indicate that the lack of intact MyD88 signaling in B cells, coupled with impaired epithelial integrity, enables commensal bacteria to function as highly pathogenic organisms, causing rapid host death.
Collapse
Affiliation(s)
- Donna Kirkland
- Department of Immunology, University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390, USA
| | | | | | | | | | | | | |
Collapse
|
687
|
The dialog between microbiota and the immune system: Shaping the partners through development and evolution. Semin Immunol 2012; 24:1-2. [DOI: 10.1016/j.smim.2011.11.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
688
|
Lee KW, Ho Hong Y, Lee SH, Jang SI, Park MS, Bautista DA, Ritter GD, Jeong W, Jeoung HY, An DJ, Lillehoj EP, Lillehoj HS. Effects of anticoccidial and antibiotic growth promoter programs on broiler performance and immune status. Res Vet Sci 2012; 93:721-8. [PMID: 22301016 DOI: 10.1016/j.rvsc.2012.01.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2011] [Revised: 12/28/2011] [Accepted: 01/03/2012] [Indexed: 11/18/2022]
Abstract
This study investigated the effects of various coccidiosis control programs in combination with antibiotic growth promoters (AGPs) on growth performance and host immune responses in broiler chickens. The coccidiosis programs that were investigated included in ovo coccidiosis vaccination (CVAC) with Inovocox or in-feed medication with diclazuril as Clinacox (CLIN) or salinomycin (SAL). The AGPs were virginiamycin or bacitracin methylene disalicylate plus roxarsone. As a negative control, chickens were non-vaccinated and fed with non-supplemented diets (NONE). All animals were exposed to used litter from a commercial broiler farm with confirmed contamination by Eimeria parasites to simulate in-field exposure to avian coccidiosis. Broiler body weights in the CVAC group were greater at 14 and 32 days of age, but not at day 42, compared with the NONE, CLIN, and SAL groups. At day 14, the SAL group showed decreased body weight and reduced ConA-stimulated spleen cell proliferation compared with the CLIN and SAL groups. In contrast, at days 34 and 43, splenocyte proliferation was greater in the CVAC and CLIN groups compared with the NONE and SAL groups. Lymphocyte subpopulations and cytokine mRNA expression levels in the intestine and spleen were also altered by the denoted treatments. Collectively, these results suggest that in ovo coccidiosis vaccination or coccidiostat drug medication programs in combination with AGPs influences chicken growth and immune status in an Eimeria-contaminated environment.
Collapse
Affiliation(s)
- Kyung-Woo Lee
- Animal Parasitic Diseases Laboratory, Animal and Natural Resources Institute, Agricultural Research Service, USDA, Beltsville, MD 20705, USA
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
689
|
Van Way CW. What's next? Nutrition care and science in the 21st century. JPEN J Parenter Enteral Nutr 2012; 36:238-47. [PMID: 22282870 DOI: 10.1177/0148607111416121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The purpose of this review is 2-fold. First, it speculates on future scientific work that will have the greatest effect on clinical practice of nutrition care. Second, it discusses the current and future state of the healthcare system, paying special attention to demographic trends and the future of healthcare reform as it will affect nutrition practice.
Collapse
Affiliation(s)
- Charles W Van Way
- Department of Surgery, Shock/Trauma Research Center, UMKC, Kansas City, Missouri 64108, USA.
| |
Collapse
|
690
|
Psychoneuroimmunology meets neuropsychopharmacology: translational implications of the impact of inflammation on behavior. Neuropsychopharmacology 2012; 37:137-62. [PMID: 21918508 PMCID: PMC3238082 DOI: 10.1038/npp.2011.205] [Citation(s) in RCA: 642] [Impact Index Per Article: 53.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The potential contribution of chronic inflammation to the development of neuropsychiatric disorders such as major depression has received increasing attention. Elevated biomarkers of inflammation, including inflammatory cytokines and acute-phase proteins, have been found in depressed patients, and administration of inflammatory stimuli has been associated with the development of depressive symptoms. Data also have demonstrated that inflammatory cytokines can interact with multiple pathways known to be involved in the development of depression, including monoamine metabolism, neuroendocrine function, synaptic plasticity, and neurocircuits relevant to mood regulation. Further understanding of mechanisms by which cytokines alter behavior have revealed a host of pharmacologic targets that may be unique to the impact of inflammation on behavior and may be especially relevant to the treatment and prevention of depression in patients with evidence of increased inflammation. Such targets include the inflammatory signaling pathways cyclooxygenase, p38 mitogen-activated protein kinase, and nuclear factor-κB, as well as the metabolic enzyme, indoleamine-2,3-dioxygenase, which breaks down tryptophan into kynurenine. Other targets include the cytokines themselves in addition to chemokines, which attract inflammatory cells from the periphery to the brain. Psychosocial stress, diet, obesity, a leaky gut, and an imbalance between regulatory and pro-inflammatory T cells also contribute to inflammation and may serve as a focus for preventative strategies relevant to both the development of depression and its recurrence. Taken together, identification of mechanisms by which cytokines influence behavior may reveal a panoply of personalized treatment options that target the unique contributions of the immune system to depression.
Collapse
|
691
|
Abstract
Accumulating evidence has made clear that experience--the knowledge an individual acquires during a lifetime of sensing and acting--is of fundamental biological relevance. Experience makes an impact on all adaptive systems, including the endocrine, immune, and nerve systems, and is of the essence, not only for the unfolding of an organisms' healthy status, but also for the development of malfunctional traits. Nevertheless, experience is often excluded from empirical approaches. A variety of complex interactions that influence life histories are thereby neglected. Such ignorance is especially detrimental for psychoneuroimmunology, the science that seeks to understand how the exquisite and dynamic interplay between mind, body, and environment relates to behavioral characteristics. The article reviews claims for incorporating experience as a member of good explanatory standing in biology and medicine, and more specifically, claims that experiential knowledge is required to enable meaningful and relevant explanations and predictions in the psychoneuroimmunological realm.
Collapse
Affiliation(s)
- Elling Ulvestad
- Department of Microbiology, The Gade Institute, Haukeland University Hospital, University of Bergen, Bergen, Norway.
| |
Collapse
|
692
|
Gravano DM, Vignali DAA. The battle against immunopathology: infectious tolerance mediated by regulatory T cells. Cell Mol Life Sci 2011; 69:1997-2008. [PMID: 22205213 DOI: 10.1007/s00018-011-0907-z] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2011] [Revised: 12/11/2011] [Accepted: 12/12/2011] [Indexed: 02/07/2023]
Abstract
Infectious tolerance is a process whereby one regulatory lymphoid population confers suppressive capacity on another. Diverse immune responses are induced following infection or inflammatory insult that can protect the host, or potentially cause damage if not properly controlled. Thus, the process of infectious tolerance may be critical in vivo for exerting effective immune control and maintaining immune homeostasis by generating specialized regulatory sub-populations with distinct mechanistic capabilities. Foxp3(+) regulatory T cells (T(regs)) are a central mediator of infectious tolerance through their ability to convert conventional T cells into induced regulatory T cells (iT(regs)) directly by secretion of the suppressive cytokines TGF-β, IL-10, or IL-35, or indirectly via dendritic cells. In this review, we will discuss the mechanisms and cell populations that mediate and contribute to infectious tolerance, with a focus on the intestinal environment, where tolerance induction to foreign material is critical.
Collapse
Affiliation(s)
- David M Gravano
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105-3678, USA
| | | |
Collapse
|
693
|
Tanoue T, Honda K. Induction of Treg cells in the mouse colonic mucosa: a central mechanism to maintain host-microbiota homeostasis. Semin Immunol 2011; 24:50-7. [PMID: 22172550 DOI: 10.1016/j.smim.2011.11.009] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
CD4+ regulatory T (Treg) cells expressing the transcription factor forkhead box P3 (Foxp3) play a critical role in maintaining immunological homeostasis. Treg cells are highly abundant in the mouse intestinal lamina propria, particularly in the colon. Recent studies using germ-free and gnotobiotic mice have revealed that specific components of the intestinal microbiota influence the number and function of Treg cells. Substantial changes in the composition of microbiota have been associated with inflammatory bowel disease. In this review, we will discuss recent findings that associate intestinal microbiota in mice with Treg responses and with the maintenance of intestinal immune homeostasis.
Collapse
Affiliation(s)
- Takeshi Tanoue
- Department of Immunology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | | |
Collapse
|
694
|
Festi D, Schiumerini R, Birtolo C, Marzi L, Montrone L, Scaioli E, Di Biase AR, Colecchia A. Gut microbiota and its pathophysiology in disease paradigms. Dig Dis 2011; 29:518-24. [PMID: 22179206 DOI: 10.1159/000332975] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The gut flora carries out important functions for human health, although most of them are still unknown, and an alteration of any of them, due to a condition of dysbiosis, can lead to relevant pathological implications. Commensal bacteria in the gut are essential for the preservation of the integrity of the mucosal barrier function and an alteration in the anatomic functional integrity of this barrier has been implicated in the pathophysiologic process of different diseases. The gut microflora plays a role in modulating the intestinal immune system; in fact, it is essential for the maturation of gut-associated lymphatic tissue, the secretion of IgA and the production of antimicrobial peptides. The enteric flora represents a potent bioreactor which controls several metabolic functions, even if most of them are still unknown. The main metabolic functions are represented by the fermentation of indigestible food substances into simple sugars, absorbable nutrients, and short-chain fatty acids. Furthermore, the gut microbiota exerts important trophic and developmental functions on the intestinal mucosa. This overview focuses briefly on the physiological role of the gut microbiota in maintaining a healthy state and the potential role played by disturbances of both the function and composition of the gut microbiota in determining important pathological conditions, such as irritable bowel syndrome, inflammatory bowel disease, metabolic syndrome, obesity, and cancer.
Collapse
Affiliation(s)
- Davide Festi
- Department of Clinical Medicine, University of Bologna, S. Orsola-Malpighi Hospital, Bologna, Italy.
| | | | | | | | | | | | | | | |
Collapse
|
695
|
Gigante G, Tortora A, Ianiro G, Ojetti V, Purchiaroni F, Campanale M, Cesario V, Scarpellini E, Gasbarrini A. Role of gut microbiota in food tolerance and allergies. Dig Dis 2011; 29:540-9. [PMID: 22179209 DOI: 10.1159/000332977] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Alterations of commensal flora may cause various gastrointestinal and extraintestinal diseases, including food intolerances and food allergies. According to the 'microflora hypothesis', alterations in the composition of gut microbiota in industrialized countries have disturbed the mechanisms of mucosal immune tolerance. Over the past few years several studies have looked for a role for probiotics in the treatment of food allergies with promising results.
Collapse
Affiliation(s)
- Giovanni Gigante
- Internal Medicine Department, Catholic University of Sacred Heart, Gemelli Hospital, Rome, Italy
| | | | | | | | | | | | | | | | | |
Collapse
|
696
|
Fismer K, Lewith G. College of Medicine: A new vision of healthcare. Eur J Integr Med 2011. [DOI: 10.1016/j.eujim.2011.09.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
|
697
|
Control of host inflammatory responsiveness by indigenous microbiota reveals an adaptive component of the innate immune system. Microbes Infect 2011; 13:1121-32. [DOI: 10.1016/j.micinf.2011.07.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Revised: 07/23/2011] [Accepted: 07/25/2011] [Indexed: 01/15/2023]
|
698
|
Schurgers E, Billiau A, Matthys P. Collagen-induced arthritis as an animal model for rheumatoid arthritis: focus on interferon-γ. J Interferon Cytokine Res 2011; 31:917-26. [PMID: 21905879 DOI: 10.1089/jir.2011.0056] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Rheumatoid arthritis (RA), an autoimmune disease causing inflammation, destruction, and deformity of the joints, affects around 1% of the world population. It is a systemic disease as patients exhibit extra-articular manifestations as well. Collagen-induced arthritis (CIA) in DBA/1 mice is one of the many animal models used to study possible pathogenic mechanisms of RA. It involves immunizing mice with collagen type II in complete Freund's adjuvant. Here we briefly review the general characteristics of RA and CIA and present an overview of data obtained by studying CIA in several gene knockout mice. In particular, detailed analysis of CIA in interferon-gamma (IFN-γ) receptor-deficient mice has pin-pointed IFN-γ as an important cytokine in the pathogenesis and has exposed new functions of IFN-γ in immunological processes. Pilot trials with exogenous IFN-γ in RA have been indicative of a beneficial effect. That improvement of the disease symptoms by IFN-γ treatment was not spectacular may be explained by the fact that RA is a heterogeneous disease in which the severity of the autoimmune disease is strongly determined by environmental factors.
Collapse
MESH Headings
- Animals
- Arthritis, Experimental/genetics
- Arthritis, Experimental/immunology
- Arthritis, Rheumatoid/immunology
- Arthritis, Rheumatoid/metabolism
- Arthritis, Rheumatoid/prevention & control
- Disease Models, Animal
- Humans
- Interferon-gamma/immunology
- Interferon-gamma/metabolism
- Interferon-gamma/pharmacology
- Mice
- Mice, Knockout
- Models, Immunological
- Receptors, Interferon/deficiency
- Receptors, Interferon/genetics
- Receptors, Interferon/immunology
- Interferon gamma Receptor
Collapse
Affiliation(s)
- Evelien Schurgers
- Laboratory of Immunobiology, Faculty of Medicine, Rega Institute, Katholieke Universiteit Leuven, Leuven, Belgium
| | | | | |
Collapse
|
699
|
Atarashi K, Honda K. Microbiota in autoimmunity and tolerance. Curr Opin Immunol 2011; 23:761-8. [PMID: 22115876 DOI: 10.1016/j.coi.2011.11.002] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2011] [Revised: 10/17/2011] [Accepted: 11/10/2011] [Indexed: 12/18/2022]
Abstract
The composition of a host's intestinal microbiota directs the type of mucosal and systemic immune responses by affecting the proportion and number of functionally distinct T cell subsets. In particular, the microbiota composition affects the differentiation of intestinal Th17 cells and Foxp3(+) regulatory T cells, both of which play critical roles in maintaining mucosal barrier functions and in controlling immunological homeostasis. In this review, we discuss the recent advances in our understanding of how the intestinal microbiota affects T cell differentiation and host susceptibility to autoimmune disease.
Collapse
Affiliation(s)
- Koji Atarashi
- Department of Immunology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | | |
Collapse
|
700
|
Bron PA, van Baarlen P, Kleerebezem M. Emerging molecular insights into the interaction between probiotics and the host intestinal mucosa. Nat Rev Microbiol 2011; 10:66-78. [PMID: 22101918 DOI: 10.1038/nrmicro2690] [Citation(s) in RCA: 415] [Impact Index Per Article: 31.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Probiotic bacteria can modulate immune responses in the host gastrointestinal tract to promote health. The genomics era has provided novel opportunities for the discovery and characterization of bacterial probiotic effector molecules that elicit specific responses in the intestinal system. Furthermore, nutrigenomic analyses of the response to probiotics have unravelled the signalling and immune response pathways which are modulated by probiotic bacteria. Together, these genomic approaches and nutrigenomic analyses have identified several bacterial factors that are involved in modulation of the immune system and the mucosal barrier, and have revealed that a molecular 'bandwidth of human health' could represent a key determinant in an individual's physiological responsiveness to probiotics. These approaches may lead to improved stratification of consumers and to subpopulation-level probiotic supplementation to maintain or improve health, or to reduce the risk of disease.
Collapse
Affiliation(s)
- Peter A Bron
- Top Institute Food and Nutrition, Nieuwe Kanaal 9A, 6709 PA Wageningen, The Netherlands
| | | | | |
Collapse
|